Curved cannula

ABSTRACT

A cannula having multiple curves, devices for creating the cannula, and methods for using the cannula having multiple curves. One of the devices comprises two dies configured to mate together to transform a straight cannula into a double-curved cannula having two curves, and a base that is configured to slideably guide the two dies from respective initial positions to a mating position.

BACKGROUND

This specification relates to cannulas, and more particularly tocannulas for performing nonsurgical procedures including nonsurgicalfacelifts.

A cannula is a thin tube, typically made of metal, that can be insertedinto the body. Cannulas can be used to perform nonsurgical percutaneousprocedures, including facelifts. In this context, the term nonsurgicalmeans a procedure that requires an incision that is substantially nolarger than the width of the cannula itself. Therefore, using a cannulato perform a nonsurgical facelift is often referred to as a minimallyinvasive procedure, which typically does not require general anesthesia.

To perform a percutaneous facelift, a cannula equipped with a puncturingtip, e.g., a needle or a trocar, can be inserted through the skin of apatient's face. The cavity within the cannula can then be used tointroduce hooked or barbed threads of an appropriate material, e.g.,polydioxanone (PDO), into the cavity created by the cannula. Thesecavities created by a cannula may be referred to as thread paths. Byapplying tension to the threads introduced into the thread paths of theskin, the skin of the patient can be lifted or tightened.

Cannulas are generally manufactured to be as straight as possible.However, this straightness can introduce suboptimal results innonsurgical procedures. In particular, a straight cannula tends togenerate a thread path that is also straight, which can lead tosuboptimal lifting results.

SUMMARY

This specification describes a double-curved cannula having multiplepreformed curves, a technique for using the cannula, and a device formaking double-curved cannulas.

Particular embodiments of the subject matter described in thisspecification can be implemented so as to realize one or more of thefollowing advantages. Using a double-curved cannula for nonsurgicalfacelifts provides a superior lifting result because the curves of thecannula can make curved paths within the skin that follow the naturalcurves of the cheek. A single cannula can be used to introduce suchcurved paths, thereby providing superior results to using straightcannulas.

The details of one or more embodiments of the subject matter of thisspecification are set forth in the accompanying drawings and thedescription below. Other features, aspects, and advantages of thesubject matter will become apparent from the description, the drawings,and the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram that illustrates a cannula having two preformedcurves and a device for bending a straight cannula into a cannula havingtwo preformed curves.

FIG. 2 illustrates using a cannula 202 having two preformed curves toperform a nonsurgical facelift.

FIG. 3A illustrates example paths 302, 304 that follow the ogee curve ofa patient's face.

FIG. 3B illustrates additional examples of curved paths that can becreated by an insertion process that involves rotating a double-curvedcannula.

FIG. 4 illustrates an exploded view of an example jig having a base andtwo matable dies.

FIGS. 5A-D illustrate hand operation of an example jig.

Like reference numbers and designations in the various drawings indicatelike elements.

DETAILED DESCRIPTION

FIG. 1 is a diagram that illustrates a cannula having two preformedcurves and a device for bending a straight cannula into a cannula havingtwo preformed curves.

In this specification, a cannula having preformed curves means that thecannula has attained, before being used in a procedure on a patient, astable shape exhibiting at least two curves that are observable to thenaked eye. Typically, a cannula having two preformed curves will haveone convex curve and one concave curve relative to a common referenceframe.

The preformed curves can be introduced into the shape of a straightcannula at any appropriate time prior to a procedure being used on apatient. For example, a cannula can be manufactured to have twopreformed curves. Alternatively or in addition, a cannula can bemodified at one stage of a manufacturing process to have two preformedcurves. As another example, a cannula can be bent by a doctor in adoctor's office just before the procedure is performed, e.g., using adevice as described in this specification in more detail below. In thisspecification, a device used to introduce preformed curves in the shapeof a cannula will be referred to as a jig.

An advantage to introducing the preformed curves at manufacturing timeis that doctors performing the procedures need not re-sterilize thecannula before use, as is the case with bending the cannula with anon-site jig.

As shown in FIG. 1, the cannula 110 has two preformed curves 112 and114. The curves 112 and 114 are oppositely convex and concave whenobserved from the same reference frame. The cannula 100 can have anyappropriate gauge for performing the procedures described in thisspecification. For example, the cannula can be a 17-gauge, 18-gauge,19-gauge, or 20-gauge cannula.

The cannulas can be any appropriate length for performing a particularpercutaneous procedure. For example, the cannula can have a length thatis appropriate based on the size of a patient's face or based on arepresentative size of a representative population of people.

As illustrated in FIG. 1, the curves 112 and 114 are substantially thesame length and have substantially the same radius. However, thedimensions of the cannula can vary. For example, curves having differinglengths and radii can be used depending on the procedure being performedand on the preferences of the provider. In some implementations, eachcurve follows an arc for at least 20 degrees. In some otherimplementations, the curves are sinusoidal. Regardless of the exactshape, the preformed curves are generally noticeable from visualinspection, and the a cannula having two preformed curves as describedis visually distinguishable from a straight cannula.

A jig 130 has two matable dies 134 and 136 and a base 132 that isconfigured to slideably guide the two matable dies from an initialposition to a mated position. The sliding action is guided by two slots131 and 133 in the base 132 that are configured to receive correspondingrails or tabs on the dies 134 and 136.

As can be observed from FIG. 1, due to elasticity of the cannulamaterial, the curves of the jig 130 are typically more pronounced thanthe preformed curves that are imparted on the cannula 110. In otherwords, in order to achieve a particular desired curvature of the cannula110, the jig 130 often has curves that are more pronounced orexaggerated relative to the desired curvature of the cannula 110.

The jig 130 can be operated by hand, e.g., by a doctor or anothermedical technician, or by machines, e.g., by one or more robots in amanufacturing facility.

As shown in FIG. 1, the jig 130 can be used to impart curves on cannulashaving a variety of configurations 140 that may or may not be used forperforming nonsurgical facelift procedures. In some implementations, thecannula 110 has a blunt, L-type tip.

FIG. 2 illustrates using a cannula 202 having two preformed curves toperform a nonsurgical facelift. In general, the cannula 202 has aleading curve and a trailing curve that arc in opposing directions. Insome implementations, the curves are on substantially the same plane.

To perform the procedure, at step 1 210, the cannula 202 having twopreformed curves is inserted at an insertion point 212 near the uppercheek. The insertion point 212 can be a predetermined distance from thelateral canthus, e.g., 1, 2, 3, or 4 cm from the lateral canthus. InFIG. 2, portions of the cannula that are underneath the skin areillustrated using dashed lines.

During a first portion of the insertion step, the leading curve of thecannula 202 follows a curved path from the insertion point 212 throughthe skin of the patient to a midway point 222 near the mid cheek. Theleading curve of the cannula 202 thus maneuvers the cannula 202 aroundthe cheekbone of the patient. As shown, at the midway point 222, theinterior of the leading curve of the cannula 202 is facing up and to theinside of the patient's face.

After reaching the midway point 222, the cannula 202 is rotated while orbefore continuing the insertion process until reaching the end point232. During this second portion of the insertion procedure, the leadingpoint of the cannula 202 is inserted through the skin from the midwaypoint 222 along a curved path to the end point 232.

During this process, the trailing curve of the cannula 202 substantiallyfollows the curved path created by the leading curve of the cannula 202during the first portion of the insertion step, e.g., the curved pathfrom the insertion point 212 to the midway point 222.

The rotation maneuver can substantially rotate the cannula 202 between90 and 270 degrees, e.g., substantially 180 degrees, about an axispassing between the leading curve and the trailing curve. When the tipof the cannula 202 reaches the end point 232, the rotation of thecannula 202 causes the interior of the leading curve of the cannula 202to be facing down and to the outside of the patient's face.

This procedure can cause the leading curve of the cannula 202 to followthe ogee curve of the patient's face. In this specification, an ogeecurve is a curve defined by the malar or cheekbone prominence. Thus, thecannula 202 can be bent to have a preformed leading curve defined by arepresentative ogee curve. The shape of the representative ogee curvecan be defined with respect to a population of patients or a measure ofcentral tendency of a population of patients.

After reaching the end point, the cannula 202 can be removed byreversing the order of steps. Upon initiating the removal process, barbson threads within the cannula 202 can latch onto skin within the curvedpaths created by the cannula 202, thereby leaving a thread within theskin along the curved path created by the cannula 202. Applying tensionto the thread left along the curved path created by the cannula 202 canprovide a superior lifting result to prior art techniques. Inparticular, the lifting direction of the skin follows the contours ofthe patient's face, thereby providing a more natural-looking result.

Typically, the procedure illustrated in FIG. 2 is repeated multipletimes to introduce threads along multiple curved paths.

FIG. 3A illustrates example paths 302, 304 that follow the ogee curve ofa patient's face.

FIG. 3B illustrates additional examples of curved paths that can becreated by an insertion process that involves rotating a double-curvedcannula. As shown, the curved paths 312, 314, and 316 follow the contourof the patient's face from an insertion point to respective end points322, 324, and 326.

Applying tension to the threads left within the curved paths 312, 314,and 216 has the effect of lifting the skin of the face along thecontours of the face, thereby providing a more natural lift than priorart techniques that use straight cannulas.

FIG. 4 illustrates an exploded view of an example jig 400 having a base410 and two matable dies 420 and 430. The example jig is an example of amechanism that can reliably bend cannulas into a same shape over andover.

As shown, the base 410 has two slots 412, 414 that are configured toreceive corresponding rails 422 a-b and 432 a-b of respective dies 420and 430. (From this perspective, the rail 432 a is indicated but notvisible). The base 410 can have any appropriate mechanism forconsistently guiding the dies 420, 430 to a mating position. Forexample, the base 410 can have tabs that correspond to the slots 412,414.

Each die 420 and 430 has one or more rails 422 a-b or 432 a-b that areconfigured to slide along the slots 412, 414 in the base 410. In theexample illustrated in FIG. 4, the rails 432 a-b and 432 a-b areT-shaped to be compatible with T-shaped slots 412, 414 in the base 410,which reduces perpendicular motion when mating the dies 420, 430.

Each die 420 and 430 is fashioned with a curved surface that defines oneor more curves. The curves of the dies 420 and 430 together are mirroredso that they fit together during the mating process. As described above,a cannula can be bent to have a leading curve defined by arepresentative curve, e.g., an ogee curve. Because of the pliability ofmetal materials, obtaining an appropriate representative curve in thecannula can require the dies 420 and 430 to have an exaggerated or morepronounced or severe curve than the desired representative curve.

Each die 420 and 430 also has a groove 424 and 434 to receive a cannulaand hold the cannula in place during the bending process. Each die 420and 430 can alternatively or in addition have any other appropriatemechanism for holding a cannula in place during the mating process,e.g., ridges or fastening components.

After placing a cannula into the jig 400, the two dies 420 and 430having curves that mirror each other are closed or otherwise pressedtogether. The action of closing together the two dies 420 and 430 causesthe metal cannula to be bent into a precise and reproducible shape. Insome cases, the dies 420 and 430 are held together for several secondsin order to set the curved shape of the metal cannula.

The closing action of the jig 400 can be performed by a machine or byhand. For example, the jig 400 can be a part of an assembly line systemin a factory. Assembly machines or robots can output straight cannulas.The cannulas can then be bent by a jig into curved cannulas. The curvedcannulas can then be sterilized and packaged for distribution.

Alternatively, the example jig 400 can be used to bend a straightcannula after manufacturing and distribution. For example, a doctor canuse the jig 400 in a clinic setting to transform a straight cannula intoa curved cannula. Typically, this process would involve resterilizingthe cannula after it is bent into shape.

FIGS. 5A-D illustrate hand operation of an example jig.

As shown in FIG. 5A, a straight cannula 502 is placed so that it isresting on the base 510 of the jig. The bending process starts byengaging the straight cannula with the grooves on the dies 520 and 530.Engaging with the grooves on the dies 520 and 530 holds the cannula inplace during the bending process.

The dies 520 and 530 are then pressed together into a mating position asshown in the sequence illustrated in FIGS. 5B and 5C. As illustrated,this process can be performed by hand. Alternatively, the process can beperformed by industrial machines in an assembly line or by one or morerobots. In some cases, the fully mated position is held for a durationlasting between 1 and 5 seconds in order to fully bend the cannula 502.

As shown in FIG. 5D, the dies are opened. In some implementations, thebase is spring-loaded so that the rails of the dies 520 and 530 areforced open when a user or a machine no longer applies inward force tothe dies 520 and 530.

As illustrated in FIG. 5D, the previously straight cannula now has twonoticeable curves imparted by the dies 520 and 530, which remain in thecannula after the dies 520 and 530 are opened. Because of the propertiesof the metal used in the cannula, the curves of the bent cannula aretypically less pronounced than the curves of the dies 520 and 530.Therefore, the dies 520 and 530 can be manufactured to have morepronounced curves that result in a cannula having curves to match aparticular representative curve, e.g., a representative ogee curve.

In addition to the embodiments described above, the followingembodiments are also innovative:

Embodiment 1 is a cannula having two preformed curves.

Embodiment 2 is the cannula of embodiment 1, wherein each of thepreformed curves follows a respective arc for at least 20 degrees.

Embodiment 3 is the cannula of any one of embodiments 1-3, wherein thetwo preformed curves are sinusoidal.

Embodiment 4 is the cannula of any one of embodiments 1-3, wherein thetwo preformed curves are convex and concave respectively.

Embodiment 5 is the cannula of any one of embodiments 1-4, wherein thetwo preformed curves comprise a leading curve and a trailing curve.

Embodiment 6 is the cannula of embodiment 5, wherein the leading curveis defined by a representative ogee curve.

Embodiment 7 is the cannula of embodiment 6, wherein the representativeogee curve is defined from a population of patients.

Embodiment 8 is a jig comprising:

two dies configured to mate together to transform a straight cannulainto a double-curved cannula having two curves; and

a base that is configured to slideably guide the two dies fromrespective initial positions to a mating position.

Embodiment 9 is the jig of embodiment 8, wherein one or more of the diescomprises a groove configured to receive the straight cannula.

Embodiment 10 is the jig of any one of embodiments 8-9, wherein the basehas one or more slots configured to guide the two dies from therespective initial positions to a mating position.

Embodiment 11 is the jig of embodiment 10, wherein the dies compriserails or tabs that are guided by the one or more slots of the base.

Embodiment 12 is the jig of any one of embodiments 8-10, wherein one ormore of the dies have a curve that is defined by a representative ogeecurve.

Embodiment 13 is the jig of embodiment 12, wherein the curves of thedies are more pronounced than the representative ogee curve such thatthe dies impart a curve on a cannula having the representative ogeecurve.

Embodiment 14 is the jig of embodiment 12, wherein the representativeogee curve is defined from a population of patients.

Embodiment 15 is a method of forming a double-curved cannula having twocurves comprising:

placing a straight cannula in a jig having two matable dies; and

moving the matable dies together into a mating position, thereby formingthe double-curved cannula.

Embodiment 16 is the method of embodiment 15, wherein placing thestraight cannula in the jig comprises resting the cannula on a base ofthe jig.

Embodiment 17 is the method of embodiment 16, further comprisingengaging the straight cannula with a groove on one of the matable ties.

Embodiment 18 is the method of any one of embodiments 15-17, wherein thedies have a curve that is defined by a representative ogee curve.

Embodiment 19 is the method of embodiment 18, wherein the curve of thedies is more pronounced than the representative ogee curve such that thedies impart the representative curve on the cannula when the dies areopened.

Embodiment 20 is the method of embodiment 18, wherein the representativeogee curve is defined from a population of patients.

Embodiment 21 is the method of any one of embodiments 15-20, whereinmoving the dies together is performed by a machine on an assembly lineor by one or more robots.

Embodiment 22 is the method of any one of embodiments 15-20, whereinmoving the dies together is performed manually.

Embodiment 23 is a method comprising performing a nonsurgical faceliftusing a cannula having two preformed curves.

Embodiment 24 is the method of embodiment 23, wherein using the cannulahaving two preformed curves comprises:

initially inserting the cannula at an initial insertion point near anupper cheek of a patient;

inserting a leading curve of the cannula along a curved path from theinsertion point to a midway point;

rotating the cannula; and

inserting a trailing curve of the cannula.

Embodiment 25 is the method of embodiment 24, wherein rotating thecannula comprises rotating the cannula between 90 and 270 degrees.

Embodiment 26 is the method of any one of embodiments 24-25, whereinrotating the cannula causes an orientation of an interior of the leadingcurve of the cannula to face down and to an outside of a patient's face.

Embodiment 27 is the method of embodiment 26, wherein before rotatingthe cannula, the orientation of the interior of the leading curve of thecannula faces up and to the inside of the patient's face.

Embodiment 28 is the method of any one of embodiments 24-27, furthercomprising:

removing the cannula along the curved path; and

applying tension to a thread left by the cannula along the curved pathto effectuate the nonsurgical facelift.

Embodiment 29 is the method of any one of embodiments 24-28, wherein thecurved path follows an ogee curve of the patient's face.

While this specification contains many specific implementation details,these should not be construed as limitations on the scope of anyinvention or on the scope of what may be claimed, but rather asdescriptions of features that may be specific to particular embodimentsof particular inventions. Certain features that are described in thisspecification in the context of separate embodiments can also beimplemented in combination in a single embodiment. Conversely, variousfeatures that are described in the context of a single embodiment canalso be implemented in multiple embodiments separately or in anysuitable subcombination. Moreover, although features may be describedabove as acting in certain combinations and even initially be claimed assuch, one or more features from a claimed combination can in some casesbe excised from the combination, and the claimed combination may bedirected to a subcombination or variation of a subcombination.

Similarly, while operations are depicted in the drawings in a particularorder, this should not be understood as requiring that such operationsbe performed in the particular order shown or in sequential order, orthat all illustrated operations be performed, to achieve desirableresults. Moreover, the separation of various system modules andcomponents in the embodiments described above should not be understoodas requiring such separation in all embodiments.

Particular embodiments of the subject matter have been described. Otherembodiments are within the scope of the following claims. For example,the actions recited in the claims can be performed in a different orderand still achieve desirable results. As one example, the processesdepicted in the accompanying figures do not necessarily require theparticular order shown, or sequential order, to achieve desirableresults.

What is claimed is:
 1. A jig comprising: two dies configured to matetogether to transform a straight cannula into a double-curved cannulahaving two curves; and a base that is configured to slideably guide thetwo dies from respective initial positions to a mating position.
 2. Thejig of claim 1, wherein one or more of the dies comprises a grooveconfigured to receive the straight cannula.
 3. The jig of claim 1,wherein the base has one or more slots configured to guide the two diesfrom the respective initial positions to a mating position.
 4. The jigof claim 3, wherein the dies comprise rails or tabs that are guided bythe one or more slots of the base.
 5. The jig of claim 1, wherein one ormore of the dies have a curve that is defined by a representative ogeecurve.
 6. The jig of claim 5, wherein the curves of the dies are morepronounced than the representative ogee curve such that the dies impartthe representative ogee curve on the cannula when the dies are opened.7. The jig of claim 5, wherein the representative ogee curve is definedfrom a population of patients.
 8. A method of forming a double-curvedcannula having two curves comprising: placing a straight cannula in ajig having two matable dies; and moving the matable dies together into amating position, thereby forming the double-curved cannula.
 9. Themethod of claim 8, wherein placing the straight cannula in the jigcomprises resting the cannula on a base of the jig.
 10. The method ofclaim 9, further comprising engaging the straight cannula with a grooveon one of the matable ties.
 11. The method of claim 8, wherein the dieshave a curve that is defined by a representative ogee curve.
 12. Themethod of claim 11, wherein the curve of the dies is more pronouncedthan the representative ogee curve such that the dies impart therepresentative curve on the cannula when the dies are opened.
 13. Themethod of claim 11, wherein the representative ogee curve is definedfrom a population of patients.
 14. The method of claim 8, wherein movingthe dies together is performed by a machine on an assembly line or byone or more robots.
 15. The method of claim 8, wherein moving the diestogether is performed manually.